Tower-shaped supporting structure

ABSTRACT

The invention describes a tower-shaped supporting structure ( 1 ), at least portions of which are hollow, with a plurality of interconnected prestressed concrete elements ( 2, 4 ), each of the prestressed elements ( 2 ) having a plurality of elongate prestressing means ( 10 ), more particularly wires or stranded cables, the majority of which are guided into an adjacent prestressed concrete element ( 4 ) and anchored there under tensile stress, characterised in that the prestressing means ( 10 ) have at least at one end a form-fitting means and the prestressing means ( 10 ) in the adjacent prestressed element ( 4 ) are anchored via at least one end anchoring element ( 12 ), which is connected to the prestressing means ( 10 ) via the form-fitting means.

TECHNICAL FIELD

The invention relates to a tower-shaped supporting structure, at least portions of which are hollow, comprising a plurality of interconnected prestressed concrete elements, wherein each of the prestressed concrete elements has a plurality of elongate prestressing means, the majority of which are guided into an adjacent prestressed concrete element and anchored there under tensile stress.

PRIOR ART

Tower-shaped supporting structures of the kind referred to initially are being widely used, particularly in wind power plants. The individual prestressing elements are commonly prefabricated, transported to the construction site and connected or braced to each other there.

Thus, EP 2 253 782 A1 discloses, for example, a tower-shaped supporting structure of the same type in which the prestressing means of the respective prestressing elements are guided into an adjacent prestressed concrete element and anchored there under tensile stress. For this purpose, the prestressed concrete elements have through-holes into which the prestressing means are inserted. The free ends of the prestressing means are then anchored so as to brace the individual prestressed concrete elements to each other.

To supplement the suitability of the reaction vessel for optimizing thermal kinetics, the pliable walls 48 have low thermal mass so as to enable rapid heat transfer. FIG. 3 is a plan view of a reaction vessel 50 in direct contact with heating members 52 and surrounded by a cooling chamber 54. The thickness of each pliable wall preferably lies in the range between approximately 0.0001 and 0.020 inch, more preferably between 0.0005 and 0.005 inch, and most preferably between 0.001 and 0.003 inch. In order to achieve this small thickness, the wall may be a film, a sheet or a moulded, machined, extruded or cast part, or any other appropriate thin and pliable structure.

The material of which the wall is made can be a polyalcohol such as polypropylene, polyethylene, polyester or other polymers, layer structures, or homogeneous polymers, metals or metal layer structures, or other thin, pliable and adaptive materials enabling high heat transfer levels, which are preferably in the form of a film or sheet. Where the vessel frame holding the walls consists of a particular material such as, e.g., polypropylene, the walls are preferably made of the same materials such as, e.g., polypropylene, with the result that the walls have the same heat expansion and cooling rates as the frame. Therefore, excessive stresses inside the materials, caused by heating or cooling, are reduced to a minimum such that the shell walls have the same

So-called wedge anchors in which the free ends of the prestressing means are wedge-clamped and thus anchored in place are commonly used as anchor means. However, these have the disadvantage of being subject to slip. As a result, the prestressing forces in the prestressing means are comparatively hard to regulate, especially as a comparatively large amount of overstress must first be applied to compensate the subsequently occurring slip. Furthermore, wedge anchorage requires for the respective prestressing means to have a relatively large excess length. This means that the respective prestressing means must be cut off manually or by means of complicated tools after the prestressing operation. This is a very laborious and sometimes also dangerous process which impedes the remaining construction work on the supporting structure.

In this regard, it must be borne in mind that hundreds of prestressing means of this kind are used on structures like those under discussion here. As a whole, the hitherto common wedge anchoring technique thus requires a high level of manual intervention and can hardly be automated.

SUMMARY OF THE INVENTION

It is therefore an object of the invention to provide a tower-shaped supporting structure of the kind referred to initially which allows the individual prestressed concrete elements to be accurately and reliably braced to each other while enabling an increased degree of automation in the production of the tower-shaped supporting structure.

According to the invention, this object is achieved by a tower-shaped supporting structure as set forth in claim 1 as well as by a method for producing a tower-shaped supporting structure as set forth in claim 13. Particularly preferred embodiments of the invention are specified in the dependent claims.

The invention is based on the idea of eliminating slip in the region of the end anchoring means when connecting or bracing the individual prestressed concrete elements to each other. For this purpose, provision is made, according to the invention, for the prestressing means in a tower-shaped supporting structure of this type to have at least at one end form-fitting means, particularly a thread, and to be anchored in the adjacent prestressed concrete element via at least one end anchoring element which is connected to the prestressing means via the form-fitting means or thread.

This makes it possible to connect the respective prestressed concrete elements to each other practically without slip and, thus, to regulate the forces and deformations occurring during bracing in an extremely accurate and reliable manner. In addition, the design of the prestressing means with a form-fitting means, particularly a thread, allows the excess length of the respective free end to be reduced to a minimum, at least at this free end, as this free end can be gripped in a form-fitting manner by an appropriate tensioning device. Due to this short excess length, the respective free end does not have to be cut off following bracing, which considerably increases the amount of work and operational safety.

It is another important advantage of the design according to the invention that bracing of the adjacent prestressed concrete elements can be automated to a significantly greater extent than in the prior art. Whereas known wedge anchoring techniques require multiple interventions, the type of anchorage according to the invention can be implemented almost entirely by an appropriate automatic prestressing machine. If it is taken into account that this work on a tower-shaped supporting structure must often be carried out at a very great height, the increased degree of automation allows further important advantages to be achieved, such as, in particular, improved occupational safety for the site staff. Not least, the type of connection and anchorage according to the invention can be realized with components that are of simple construction and accordingly available at low cost.

According to a further embodiment of the invention, provision is made for the end anchoring elements to be accessible from the cavity inside the tower-shaped supporting structure. Not only does this simplify the construction process, but it also effectively protects the end anchors of the supporting structure against weathering action, thus allowing the durability of the supporting structure to be increased and the corrosion protection requirements for the components to be lowered.

Although it is, in principle, possible for the end anchoring elements to be supported directly on the concrete of the prestressed concrete elements, provision is made, according to a further embodiment of the invention, for each of the end anchoring elements to be supported in the concrete via a supporting element which is preferably embedded in the concrete. As a result, the high local forces are evenly transferred into the concrete, which reduces stress concentrations in the concrete and additionally also reduces deformations due to creep and shrinkage. In addition, the required transverse tension reinforcement and/or gap reinforcement can possibly be reduced. Furthermore, the supporting element may provide a contribution to avoiding eccentricities in the corresponding prestressing means. The supporting element may be designed in a variety of different ways, with a dome-like shape having proven to be particularly advantageous.

According to a further development of the invention, it is moreover provided for at least portions of the prestressing means to be optionally anchored in the insertion channels via a bonding compound. This results in a particularly even transfer of the anchoring and prestressing forces. At the same time the prestressing means are protected from the environment, more particularly corrosion. In addition, the anchoring means may optionally be unscrewed and reused after the bonding compound has cured, which is not negligible in view of the extremely high number of prestressing and anchoring means. On the other hand, the use of unbonded prestressing means, which is optionally also possible, offers the advantage of simplifying the disassembly of the supporting structure.

When injecting a bonding compound into the insertion channels, it is of decisive importance that the insertion channels be completely filled with the bonding compound in order to achieve the desired anchoring and protective effect. In view hereof, provision is made, according to a further embodiment of the invention, for the end anchoring elements to have a through-hole (e.g., a slot) for exit of bonding compound. In this way, the bonding compound can be injected from the lower end of the insertion channels until it exits through the through-holes of the end anchoring elements provided at the upper end of the insertion channels. The through-hole in the end anchoring elements thus has a dual function, i.e., on the one hand, of facilitating complete filling and, on the other hand, of providing a full-fill control mechanism.

On the other hand, it may be advantageous within the scope of the invention to purposefully not provide a bond between prestressing means and prestressed concrete elements at specific points. In view hereof, provision is made, according to a further embodiment of the invention, for the bond between the prestressing means and the prestressed concrete elements to be weakened or disrupted at least adjacent to a connection joint between prestressed concrete elements. This allows the free expansion length of the respective prestressing means to be clearly increased such that considerably greater prestressing forces can be applied without posing a threat to the concrete of the respective prestressed concrete elements. In addition, it is also possible by purposefully omitting the bond (“debonding”) to adapt the prestressing force distribution to the respective concrete cross-section, for example in areas in which the concrete cross-section of the prestressed concrete elements is larger or smaller.

According to a further embodiment of the invention, provision is moreover made for the prestressed concrete elements to comprise insertion channels for insertion of prestressing means of adjacent prestressed concrete elements. The present invention is not, therefore, based on “external prestressing”, but is preferably aimed at guiding the prestressing means through the respective prestressed concrete elements. This enables an even distribution of the prestressing forces while having a comparatively low number of prestressing means. It is particularly preferred thereby for the cross-section of the insertion channels to increase in a direction opposite to the insertion direction of the prestressing means. This considerably simplifies insertion of the prestressing means into the insertion channels. The insertion channels can be produced, for example, by using appropriate die rods. As an alternative, however, sheaths or the like can also be provided, with corrugated sheaths being particularly suitable for achieving a good bond.

The prestressed concrete elements can, in principle, be of any basic shape within the scope of the present invention. According to a further embodiment of the invention, provision is made for the prestressed concrete elements to be designed in a ring shape (e.g. as rotationally symmetric elements such as cylinders, cones or paraboloids), resulting in particularly advantageous load-bearing characteristics as well as in a simple manufacturing process. As an alternative, provision is made, according to a further embodiment of the invention, for the prestressed concrete elements to be designed in a ring segment shape. This simplifies transport of the prestressed concrete elements, and the prestressed concrete elements can be cast in place horizontally in a classical stressing bed. Not only does this facilitate the production process, but it also enables smooth contact surfaces on the later upper side and underside of the prestressed concrete elements.

Furthermore, provision is made, according to a further embodiment of the invention, for the prestressing means to be arranged in the respective prestressed concrete element in at least two layers. This makes it possible to use comparatively thin prestressing means, which in turn clearly facilitates threading the prestressing means into the adjacent prestressed concrete elements and tensioning and anchoring the prestressing means. Another result is a particularly even distribution of the prestressing forces within the supporting structure. Layers of prestressing means are thereby understood as meaning layers extending in parallel to the outer circumferential wall of the respective prestressed concrete element.

It is, in principle, possible within the scope of the present invention for the entire tower-shaped supporting structure to substantially consist of prestressed concrete elements. Likewise, however, the present invention also enables hybrid constructions in which, for example, a lower region of the tower-shaped supporting structure is composed of prestressed concrete elements, while an upper region of the tower-shaped supporting structure is formed by one or more steel sections. In view hereof, provision is made, according to a further embodiment of the invention, for at least one prestressed concrete element to be connected to an adjacent steel tower section such that the majority of elongate prestressing means are guided into the adjacent steel tower section and anchored there under tensile stress. Thus, the same basic connecting principle is utilized, and therefore the advantages described above can be obtained in principle. Debonding of the prestressing means is, however, of particular importance for this connection since the small extensions or elongations that are commonly available for a connection with a steel tower section can be increased by targeted debonding in the corresponding prestressed concrete element, such that high prestressing forces can be applied without damaging the concrete. In addition, the integration of steel tower sections often requires even higher prestressing forces than are required for a connection between prestressed concrete elements.

In order to reliably enable these high connecting forces, provision is made, according to a further embodiment of the invention, for additional anchoring means to be provided which are anchored in the prestressed concrete element in a form-fitting manner, guided to the adjacent steel tower section and anchored there under tensile stress. Use is thus made of a combination of, on the one hand, prestressing means which at the same time ensure that prestress is applied to the respective prestressed concrete members, and, on the other hand, anchoring means which are merely anchored in the prestressed concrete element in a form-fitting manner. This allows a targeted gradation of the prestressing and anchoring forces to be achieved while reliably connecting the structural members.

According to a further embodiment of the invention, provision is furthermore made for the adjacent steel tower section to comprise a concrete section, particularly a concrete ring, through which the elongate prestressing means and optionally anchoring means are guided. Due to the additional concrete section, the surface pressure on the joint can be reduced, whilst at the same time increasing the stiffness of the steel tower section. Furthermore, especially when there is a concrete ring, the lateral strain of the concrete ring caused by the prestressing forces results in excess pressure on the concrete surrounded by steel, allowing high loads to be applied. It is particularly preferred in this respect for the concrete section to be also connected in a form-fitting manner to the steel of the adjacent tower section, thus resulting in a very stiff and reliable overall connection with minimal slip.

A method according to the invention for producing a tower-shaped supporting structure is defined in claim 13. As already stated above, this method enables a high degree of process automation and a low-slip, and thus reliable, connection between the respective prestressed concrete elements or tower sections. Here it is particularly preferred for the prestressed concrete elements to be vertically cast in place and to be preferably made from self-compacting concrete.

Vertical concrete casting may, however, pose the problem of an uneven upper side of the prestressed concrete elements, as smoothing of the upper side is difficult or impossible on account of the protruding prestressing means. In view hereof, provision is made, according to a further embodiment of the invention, for the prestressed concrete elements to be provided with a self-levelling compound on their upper side after the casting process. This results in a precisely level surface of the prestressed concrete elements, allowing them to be stacked on top of each other on the construction site without reliable reprocessing operations or levelling measures.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic, partial sectional view of an embodiment of the tower-shaped supporting structure according to the invention;

FIG. 2 schematically shows the vertical production of a prestressed concrete element for a tower-shaped supporting structure according to the invention;

FIG. 3 is a schematic view of a detail from FIG. 2;

FIG. 4 schematically shows a connection between a prestressed concrete element and a steel tower section;

FIG. 5 schematically shows a further connection between a prestressed concrete element and a steel tower section.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Preferred embodiments of the invention will now be described in detail with reference to the accompanying drawings.

FIG. 1 schematically shows a partial sectional view of a tower-shaped supporting structure 1 according to the present invention. The tower-shaped supporting structure may serve a variety of purposes within the scope of the present invention and also, for example, as a supporting structure for a wind power plant. The tower-shaped supporting structure 1 is built by stacking a plurality of prestressed concrete elements 2, 4 on top of each other and bracing them together, with each of the prestressed concrete elements 2, 4 comprising a plurality of elongate prestressing means 10 in the form of tension wires or strands. As can best be seen from FIG. 1, the prestressing means 10 of the prestressed concrete element 2 protrude beyond the latter on the upper side thereof (on the right in FIG. 1) and are guided into the adjacent prestressed concrete element 4 and anchored there under tensile stress. In this arrangement, all or just a plurality of the respective prestressing means can be anchored in the adjacent prestressed concrete element 4.

Each of the prestressing means 10 has at its anchoring end a form-fitting means, which in the present embodiment is designed as a thread but may also, for example, be designed like a ribbing, and each of the prestressing means 10 is anchored in the adjacent prestressed concrete element 4 via an end anchoring element 12 which in the present embodiment is designed as a tension nut. This tension nut is screwed onto the thread of the prestressing means 10. However, it is also possible to use end anchoring elements that are pressed onto the form-fitting means.

Connecting and bracing of the prestressed concrete elements 2 and 4 is accomplished, for example, as follows. The prestressed concrete element 2 is at first vertically positioned such that the free ends of the prestressing means 10 are vertically upright and the region of the joint 32 is oriented horizontally. The adjacent prestressed concrete element 4 is then placed on top of the prestressed concrete element 2 using a crane, such that the prestressing means 10 of the prestressed concrete element 2 are inserted into through-holes in the adjacent prestressed concrete element 4 until the adjacent prestressed concrete element 4 finally comes to rest on the prestressed concrete element 2 in the region of the joint 32. In this condition, the threaded free ends of the prestressing means 10 protrude to some extent from the through-holes of the adjacent prestressed concrete element 4. The end anchoring elements 12 are now screwed onto the prestressing means 10, and the free ends of the prestressing means 10 are gripped by an appropriate tensioning device such as, for example, a hydraulic press. The thread of the prestressing means 10 makes it possible that the prestressing means 10 only need to protrude to a minimal extent to be reliably gripped by the tensioning device.

The tensioning device then applies a defined amount of tensile stress to the prestressing means 10. After the defined amount of tensile stress has been reached, the anchoring elements 12 or tension nuts 12 are tightened so as to abut the supporting elements 14, thereby “freezing” the state of prestress induced by the tensioning device. The tension force of the tensioning device can now be released and the anchoring elements 12 ensure without play that the state of prestress is maintained between the prestressed concrete elements 2 and 4.

Although this prestressing operation can be performed by various discrete devices, it is advantageously possible within the scope of the invention to carry out most of the described steps by means of an automated prestressing and screwing device.

The end anchoring elements 12 are accessible from a cavity 1′ (at the bottom of FIG. 1) inside the tower-shaped supporting structure 1, with the tower-shaped supporting structure being designed, for example, as a hollow tower with circular or any other cross-sectional shape.

The end anchoring elements 12 or tension nuts are respectively supported in the concrete via a supporting element 14 which in the present embodiment is embedded in the concrete. The supporting element 14 may have different shapes, it being, however, preferably designed like a dome or “bell” which ensures a uniform load transfer into the concrete.

In addition, the prestressing means 10 are optionally anchored in the prestressed concrete element 4 in the region between the joint 32 and the end anchoring elements 12 via a bonding compound (for example, a bonding mortar). This bonding compound can, for example, be subsequently injected into the corresponding cavities in the prestressed concrete element 4. The end anchoring elements 12 preferably have a through-hole (e.g., slot), not shown in detail, for exit of bonding compound 16, to facilitate the injection and to ensure a complete fill. Besides providing uniform anchorage, this bonding compound also ensures reliable corrosion protection, it being, however, also possible to take other, alternative or additional, corrosion protection measures such as, for example, greasing, coating, etc. Furthermore, the end anchoring elements 12 may be appropriately covered to further improve the corrosion protection.

By contrast, in the region identified as “a” in FIG. 1, the bond between the prestressing means 10 and the prestressed concrete element 2 is weakened or even disrupted adjacent to the connection joint 30 (“debonding”). This allows higher elongation values of the prestressing means to be achieved, thus avoiding damage to the concrete when tensioning the prestressing means 10.

As can be seen from FIG. 1, the prestressing means 10 in the present embodiment are arranged in two layers in the respective prestressed concrete element 2, 4. As a result, high prestressing forces can be applied in the tower-shaped supporting structure 1, with it being possible for the tower-shaped supporting structure 1 to be designed with a larger cross-section in each of the end anchoring regions of the prestressing means 10, as is shown in FIG. 1. So that a centred prestressing force can be ensured in those regions as well, one or more prestressing means 10 can be “debonded”, as required.

One possible method for producing the prestressed concrete elements 2, 4 is schematically represented in FIG. 2. In this method, the prestressed concrete elements 2, 4 are vertically cast in place, with it being common practice to first build large-sized, e.g. cylindrical, outer and inner formworks and to additionally provide appropriate flange plates 40 for bracing the prestressing means 10 therebetween. The formwork is then filled with suitable concrete, preferably self-compacting concrete. Once the concrete has reached sufficient strength, the prestressing means 10 can be detached from the flange plates 40 such that the prestressing force is transferred into the prestressed concrete elements 2. Furthermore, the supporting elements 14 are already embedded in concrete at this stage. It is preferred thereby for the cross-section of the through-holes 20 to become larger from top to bottom.

Furthermore, a self-levelling compound 8 can be applied to the upper side of the prestressed concrete elements 2, 4 after the casting process. This levelling compound is an ultra-low viscosity and therefore self-levelling liquid, giving a precisely horizontal surface even in the region of the prestressing means 10 protruding from the concrete, without any additional measures having to be taken. This allows the respective prestressed concrete elements 2, 4 to be accurately placed on top of each other.

The detail I shown in FIG. 2 is depicted on an enlarged scale in FIG. 3. FIG. 3 shows that through-holes 20 into which the prestressing means 10 can later be inserted are provided during the production of the prestressed concrete elements 2. These through-holes 20 may be provided, for example, by way of sheaths or also by appropriate die rods, with it being possible to pull out the die rods after an initial setting of the concrete, to form the through-holes 20. Auxiliary tubes 20′ may be provided for proper alignment of the die rods (not shown) (cf. FIG. 3).

The connection between a prestressed concrete element 2 and an adjacent steel tower section is schematically shown in a partial sectional view in FIG. 4. This connection is based on the same basic principle as a connection between two prestressed concrete elements, i.e. in that the prestressing means 10 of the prestressed concrete element 2 are guided into the adjacent steel tower section 6 and anchored there under tensile stress. So that the prestressing means 10 can be elongated to a sufficient extent when tensioned, they are “debonded” in this configuration in the region of the connection joint 34 across the length identified as “a”, which can be a length of up to 1 metre and over. Furthermore, additional anchoring means 30 are provided in this embodiment, which are anchored in the prestressed concrete element 2 in a form-fitting manner, guided to the adjacent steel tower section 6 and equally anchored there under tensile stress. These additional anchoring means 30 are also debonded in the upper region. They can be formed by threaded rods with tension nuts, or the like.

Another configuration of a connection between a prestressed concrete element 2 and an adjacent steel tower section 6 is schematically shown in FIG. 5. This corresponds in terms of its basic principle to the embodiment shown in FIG. 4. However, the adjacent steel tower section 6 in FIG. 5 comprises a concrete section 6′, particularly a concrete ring, through which the prestressing means 10 and optionally anchoring means are guided. For reasons of manufacturing engineering, the form section 6 is rotated 180 degrees and vertically aligned, and the concrete ring, preferably of self-compacting concrete, is cast from above onto the steel ring. In addition, a self-levelling compound 8 is applied which automatically ensures plane parallelism between the flange of the tower section 6 and the stone surface of the concrete ring 6′. The concrete ring 6′ (beneath the welded-in steel ring) is also connected in a form-fitting manner to the steel of the tower section 6, for example by head bolts (on the right in FIG. 5) or by a corrugated or ribbed inner surface of the tower section 6 (on the left in FIG. 5). This leads to a particularly stiff connection between adjacent tower sections as well as to high durability. 

1. A tower-shaped supporting structure, at least portions of which are hollow, comprising a plurality of interconnected prestressed concrete elements wherein each of the prestressed concrete elements has a plurality of elongate prestressing elements, the majority of which are guided into an adjacent prestressed concrete element and anchored there under tensile stress, characterized in that the prestressing elements have at least at one end form-fitting and the prestressing elements are anchored in the adjacent prestressed concrete element via at least one end anchoring element which is connected to the prestressing elements via the form-fitting means.
 2. The tower-shaped supporting structure according to claim 1, characterized in that the end anchoring elements are accessible from a cavity inside the tower-shaped supporting structure.
 3. The tower-shaped supporting structure according to claim 1, characterized in that each of the end anchoring elements is supported in the concrete via a supporting element which is preferably embedded in the concrete.
 4. The tower-shaped supporting structure according to claim 1, characterized in that at least sections of the prestressing elements are additionally anchored in the prestressed concrete element via a bonding compound.
 5. The tower-shaped supporting structure according to claim 4, characterized in that the end anchoring elements have a through-hole for exit of the bonding compound.
 6. The tower-shaped supporting structure according to claim 1, characterized in that the bond between the prestressing elements and the prestressed concrete elements is weakened or disrupted at least adjacent to a connection joint between prestressed concrete elements.
 7. The tower-shaped supporting structure according to claim 1, characterized in that the prestressed concrete elements comprise insertion channels for insertion of prestressing elements of adjacent prestressed concrete elements, wherein the cross-section of the insertion channels increases in a direction opposite to the insertion direction of the prestressing elements.
 8. The tower-shaped supporting structure according to claim 1, characterized in that the prestressed concrete elements are designed in a ring shape or ring segment shape.
 9. The tower-shaped supporting structure according to claim 1, characterized in that the prestressing elements are arranged in the respective prestressed concrete elements in at least two layers.
 10. The tower-shaped supporting structure according to claim 1, characterized in that at least one prestressed concrete element is connected to an adjacent steel tower section such that the majority of elongate prestressing elements are guided into the adjacent steel tower section and anchored there under tensile stress.
 11. The tower-shaped supporting structure according to claim 10, characterized in that additional anchoring means are provided which are anchored in the prestressed concrete element in a form-fitting manner, guided to the adjacent steel tower section and anchored there under tensile stress.
 12. The tower-shaped supporting structure according to claim 10, characterized in that the adjacent steel tower section comprises a concrete section comprising a concrete ring, through which the elongate prestressing elements and anchoring means are guided and which is also connected to the steel of the tower section in a form-fitting manner.
 13. A method for producing a tower-shaped supporting structure according to claim 1, said method comprising the steps of: producing prestressed concrete elements each having a plurality of elongate prestressing elements, connecting a prestressed concrete element to an adjacent prestressed concrete element such that the majority of the prestressing elements of the prestressed concrete element are guided into the adjacent prestressed concrete element, tensioning the prestressing elements guided into the adjacent prestressed concrete element, and tightening the anchoring elements such that the prestressing elements are anchored in the adjacent prestressed concrete element under tensile stress.
 14. The method according to claim 13, characterized in that the prestressed concrete elements are vertically cast in place and are made from self-compacting concrete.
 15. The method according to claim 14, characterized in that the prestressed concrete elements are provided with a self-levelling compound on their upper side after the casting process.
 16. The tower-shaped supporting structure of claim 1, characterized in that the elongate prestressing elements comprise wires or strands.
 17. The tower-shaped supporting structure of claim 1, characterized in that at one end the form-fitting means comprise a thread.
 18. The method of claim 13, characterized in that the elongate prestressing elements comprise wires or strands. 